Snapchat's market value has dropped by US$800 million (NZD$1.1 billion) since Rihanna told fans to delete the app on Thursday.
- Fans deleting Snapchat at Rihanna's urging
- Snapchat apologises for violent Chris Brown and Rihanna ad
- Snapchat shares plummet after Kylie Jenner indicates its demise
"SNAPCHAT I know you know you ain't my fav app out there! But I'm just trying to figure out what the point was with this mess!" the singer wrote on Instagram on Thursday.
"You spent money to animate something that would intentionally bring shame to [domestic violence] victims and made a joke of it. Shame on you."
The 'Umbrella' hitmaker was referring to an in-app commercial for a smartphone game called 'Would You Rather?'
"Would you rather slap Rihanna or punch Chris Brown?" it read, accompanied by photos of the two musicians.
Snapchat was criticised for showing the ad by people who said it clearly referenced a famous incident of domestic violence between the pair.
In 2009, Brown savagely assaulted then-girlfriend Rihanna in a car. He repeatedly hit, choked and bit her as well as threatened to kill her. She was left badly bruised with a split lip, and Brown was charged and sentenced to five years of probation.
As a result, Snapchat removed the ad and apologised.
"The advert was reviewed and approved in error, as it violates our advertising guidelines," the company told the BBC.
Just days after Rihanna's condemnation, Snapchat stocks dropped 4.7 percent, costing the app US$800 million (NZD$1.1 billion).
This is the latest in a string of bad news for the app, which has seen a drop in use with the introduction of its latest update.
In February, Kylie Jenner - once a prolific Snapchat user - announced she no longer used the app, prompting a massive stock downturn.